Radiola network lamp `` Riga T-51 ''.
Network tube radiosDomesticSince the beginning of 1950, the radio network lamp "Riga T-51" has been produced at the Riga plant "Radiotekhnika". Perhaps the highest achievement of household radio receiving equipment in the early fifties in the USSR was the top-class console radio "Riga T-51", developed at the Riga plant "Radiotekhnika" in 1949. She absorbed all the experience of production and theoretical developments of that time in the field of consumer radio. The radiola is assembled in a case with a size of 1300x500x1000 mm and consists of a turntable with an automatic change of ten records (since the beginning of production, they produced radios with a turntable without an automatic change of records) and an electronic part on the 21st lamp. The electrical and acoustic parameters of the radio were high, which was ensured by the following circuit solutions: a complex acoustic unit of three low-frequency heads and one horn high-frequency head; powerful output push-pull stage on 4 tubes of 6P3S type (2 in a pair); deep control of timbres for bass and treble frequencies and loudness; three-loop IF filters with automatically variable bandwidth depending on the input signal level; efficient AGC system; block for silent tuning. The radiola was difficult to manufacture, expensive in price, and was not launched into mass production. To date, several copies of such a radio have survived. One of the radios presented to J.V. Stalin is (in working order) in the Polytechnic Museum of the city of Moscow. One copy was donated to Mao Tse Tung and is in China. The third radio tape is in the collection of the Radio Engineering Museum in Riga. On the site there are photographs of a radio from the Polytechnic Museum and the Museum of the Radio Engineering Production Association. The radio tape uses motley lamps. For example, 6K7 lamps are installed in the IF path, and the local oscillator is assembled on a rare, for those times finger-type 6Zh3P. All the others are single-capped octal lamps, common in those years. Here is a list of lamps that with EPU generally consumed a power of 270 watts from the mains: 6K4P, 6A7, 6K7 (4), 6Zh3P, 6P6S, 6B8, 6X6S, 6S5 (2), 6N8S, 6P3S (4), 6E5S, 5TS4S (3 ). Wave ranges: DV, SV, KV-1 13 m, KV-2 16 m, KV-3 19 m, KV-4 25 m, KV-5 31 m, KV-6 41 m, KV-7 49 m. the radio "Riga T-51" was made - it is not known, but at least several dozen were.
